Effect of wheat bran fiber on the development of mammary tumors in female intact and ovariectomized rats treated with 7,12-dimethylbenz(a)anthracene and in mice with spontaneously developing mammary tumors.
We examined the effect of consumption of graded increases of dietary fiber (soft white wheat bran) on the development of mammary gland carcinomas in intact female Sprague-Dawley rats during the promotion stage of carcinogenesis, induced with 7,12-dimethylbenz(a)anthracene (DMBA). The percent of rats with mammary carcinomas, the total number of mammary carcinomas and the mean number of mammary carcinomas per rat were reduced significantly at all fiber levels examined compared to rats fed a control diet. Inclusion of 9.6% fiber in the diets of ovariectomized rats that had been treated with a single i.v. dose of 2.5 mg DMBA/100 g body weight 2 weeks prior to removal of the ovaries resulted in a significant decrease of carcinomatous and benign mammary tumors compared to ovariectomized rats fed a control diet. Development of spontaneous mammary carcinomas in virgin C3H/HeOuJ female mice and growth of a transplantable mammary gland tumor in such mice were reduced by inclusion of 9.6% fiber in the diet, a reduction that was significant or just barely missed significance, depending on the source of the fiber. Our observations provide evidence that inclusion of soft white wheat bran in the diet is effective in the suppression of mammary gland tumorigenesis in an array of experimental animal models.
Zile
M H
MH
Department of Food Science and Human Nutrition, Michigan State University, East Lansing 48824, USA. zile@pilot.msu.edu
Welsch
C W
CW
Welsch
M A
MA
D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D002273:Carcinogens; D002455:Cell Division / Q000187:drug effects; D004043:Dietary Fiber / Q000627:therapeutic use*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005260:Female; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D051379:Mice; D008809:Mice, Inbred C3H; D009368:Neoplasm Transplantation; D009376:Neoplasms, Hormone-Dependent / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D010052:Ovariectomy; D010053:Ovary / Q000502:physiology* / Q000601:surgery; D051381:Rats; D017207:Rats, Sprague-Dawley; D014908:Triticum; D014407:Tumor Cells, Cultured
D002273:Carcinogens; D004043:Dietary Fiber; D015127:9,10-Dimethyl-1,2-benzanthracene